1. Field of the Invention
The present invention relates to a system and method for providing network data and system upgrades to individual devices within an ad-hoc network without requiring network-wide information broadcasts. More particularly, the present invention relates to a system and method for creating and broadcasting requests for data and upgrades between adjacent devices, wherein an individual device can update system parameters from information provided by adjacent devices, where such transfers are authorized.
2. Description of the Related Art
In recent years, a type of mobile communications network known as an “ad-hoc” network has been developed. In this type of network, each user terminal (hereinafter “mobile node”) is capable of operating as a base station or router for other mobile nodes, thus eliminating the need for a fixed infrastructure of base stations. Accordingly, data packets being sent from a source mobile node to a destination mobile node are typically routed through a number of intermediate mobile nodes before reaching the destination node.
More sophisticated ad-hoc networks are also being developed which, in addition to enabling mobile nodes to communicate with each other, as in a conventional ad-hoc network, further enable the mobile nodes to access a fixed network and communicate with other types of user terminals, such as those on the public switched telephone network (PSTN) and on other networks, such as the Internet. Details of these types of ad-hoc networks are described in U.S. patent application Ser. No. 09/897,790 entitled “Ad Hoc Peer-to-Peer Mobile Radio Access System Interfaced to the PSTN and Cellular Networks”, filed on Jun. 29, 2001, in U.S. patent application Ser. No. 09/815,157 entitled “Time Division Protocol for an Ad-Hoc, Peer-to-Peer Radio Network Having Coordinating Channel Access to Shared Parallel Data Channels with Separate Reservation Channel”, filed on Mar. 22, 2001, and in U.S. patent application Ser. No. 09/815,164 entitled “Prioritized-Routing for an Ad-Hoc, Peer-to-Peer, Mobile Radio Access System”, filed on Mar. 22, 2001, the entire content of each being incorporated herein by reference.
Generally, all nodes in a wireless ad-hoc peer-to-peer network provide similar services and functionality. Although each node can provide similar services, the workload is typically distributed across many nodes rather than centralized at a single location in the peer-to-peer network. Therefore peer-to-peer networks distinguish themselves from infrastructure networks where one or more nodes offer a superset of the functionality of the rest of the network. Infrastructure nodes in these networks typically can handle Dynamic Host Configuration Protocol (DHCP), Address Resolution Protocol (ARP), as well as other services that depend on broadcast traffic. Dynamic Host Configuration Protocol is defined by IETF RFC 2131 and 2132, and is used by a client node to automatically obtain network settings from a central server. These network settings include the client's IP address, the address of Domain Name Servers (DNS), the IP address of default gateways, and many other network settings. Address resolution protocol is defined by STD 0037 and RFC 0826, and is used by a network node to map IP addresses to MAC addresses so IP traffic can be delivered to specific hardware. These infrastructure nodes are normally discovered by broadcast traffic advertisements from their client nodes in a network.
Peer-to-peer networks typically do not contain specialized infrastructure nodes. The IEEE 802.11 standard offers a peer-to-peer mode in addition to an infrastructure mode. Details of the 802.11 standards are set forth in ISO/IEC 8802-11, ANSI/IEEE 802.11 “Information Technology—Telecommunications and Information Exchange Between Systems—Local and Metropolitan Area Network Specific Requirements”, Part 11: Wireless Medium Access Control (MAC) and Physical Layer (PHY) Specifications, the entire contents of which being incorporated herein by reference. Also, a description of the 802.11 standard is found in a book by Bob O'Hara and Al Petrick entitled IEEE 802.11 Handbook: A Designer's Companion, IEEE, 1999, the contents comprising this description being incorporated herein by reference.
Although broadcast communication may be used to identify and configure nodes within the ad-hoc network, wireless ad-hoc routing networks typically avoid repeating broadcast traffic in an effort to avoid “broadcast storms” which can flood the transmission medium with traffic and cripple the ability of the network to perform. Broadcast traffic reception is usually limited to nodes in the immediate listening area of the transmitting node. Since ARP and DHCP depend on broadcast traffic, ad-hoc routing networks sometimes “tunnel” this broadcast traffic in directed packets to known infrastructure nodes where it can be handled. Traditional non-ad-hoc networks do not encounter the broadcast problem because their nodes communicate directly with each other.
However, wireless peer-to-peer ad-hoc routing networks do not contain infrastructure nodes and therefore do not have the option to tunnel their broadcast traffic. Hence, DHCP, ARP and other broadcast network protocols must be handled in another way. In a traditional wired network, system information is usually broadcast to all devices, while upgrades are sent individually from a central location. In an ad-hoc network, however, it is undesirable to broadcast to all devices of the network since the network could become flooded. Accordingly, a need exists for a system and method where adjacent devices within the ad-hoc network, as well as the infrastructure, may be used to distribute system information directly to adjacent devices upon request without the need for network-wide broadcasts.